This invention relates to a low modulus damping film, and more particularly to a coil winding support for superconducting generator applications.
Superconducting generator applications require fast spin-up and rapid excitation. This start-up requirement necessitates a high field, high current advanced conductor such as Nb.sub.3 Sn, and a winding design which offers uniform mechanical support to prevent conductor motion. A fully epoxy impregnated winding of multistranded Nb.sub.3 Sn conductor satisfies both of these requirements. U.S. Pat. No. 3,991,333 shows a typical superconductive generator of this type, showing the use of Mylar inserted between each winding and its adjacent supports, to provide electrical insulation for the windings.
The epoxy-impregnated winding, however, must be rigidly supported with additional precompression to accommodate the centrifugal forces. As a result the coil winding support for a satisfactory design must be intimately interfaced with the impregnated winding. High shear strains can thus be transferred to the coil module which may facture and degrade the winding operation.
U.S. Pat. No. 4,037,312 to Deis discloses an insulating material of a layer of phenolic modified polyvinyl formal covered or coated with a bonding material of epoxy applied to a wires of a cable in a superconductive rotor coil. U.S. Pat. Nos. 3,662,461 to Lake, 3,705372 to Gotal and 4,467,303 to Laskaris are also of interest.